By Bob Bath
In April 2009 I bought a copy of Garden Rail while on holiday and found an article on a 7/8″ scale Spence Guinness Loco built by Peter Angus Locomotives. I just fell in love with it. There was no way I could, (1) afford it and (2) I wanted one in sixteen mill. So I started researching it on the internet where there is plenty of information but no drawings of any kind. Having discussed this with members of my local group. Edward Hodson said he would look through the library archives at the NGRS. He came up trumps with a drawing published in The Mechanical Engineer of 1888 and it was drawn 1/20 scale. So I set about drawing one using a twin cylinder double acting oscillating engine with a gear drive to the top jack shaft. After a lot of head scratching and hours going blind in front of the computer screen, enough was laid out to make a start. The foot wells and frames were made first along with the wheels and axles. Then the coupling rods and fly cranks. It was then taken to the club track and pushed round for a few hours to run the motion work in.
Next came the boiler….
This then gave me an indication of how much room there was to play with for the motor and pipe work. Due to the very small diameter of the chimney I decided to feed the exhaust down the side of the boiler and out underneath. All was going well until the motor was fitted, it was then apparent that the gear on the jack shaft would not allow the filler valve to be fitted. Attempting to drill out the bush to plug the boiler the drill grabbed and went straight through the burner tube. Cue second modified boiler to take the filler valve in the new position.
The picture above shows a top view with the motor fitted and the original boiler. Still very crude at this stage. The gas tank and valve were straightforward.
After finding how hot the tank got when steaming I had to add some insulation between the tank and the frame side. This in turn has caused the loco to 1/16″ wider than scale. In the next picture the motor is nearly in its final form, gone are the coil springs that held the cylinders down and replaced with a piano wire retainer that runs under the motor.
The reason for this was I decided to make the top covers as per the real thing and the top spring on the cylinder stuck up to far. The lubricator and boiler fittings were then made and it was run on air. It ran in a very “lumpy” fashion – the problem was traced to a being port not quite drilled through. The next big even was the steam up. This was carried out on my small stretch of test track in the garden. It lit first time but it soon became apparent that all was not well when the solder on the smokebox door hinges melted. After cutting a slot in the bottom of the smokebox to allow a bit more air flow I tried again – this time the flame came out of the slot and melted the sleepers! A redesigned burner much smaller with some air holes in the plug at the rear had the desired effect. I continued to run it several times over the next month ironing out all the small problems There are a couple of videos on youtube taken by myself and Dave Watkins.
One worrying aspect of this running was the rust forming on the frame where the steam exhausted. It was now September and I was to go on holiday again this time visiting the narrow gauge railways of North Wales. Knowing that No 13 was in the museum at the Talyllyn I took my loco with me with the intention of asking if I could photograph the two together. They were only too pleased to accommodate me.
This also allowed me to photograph the real thing and sort out a few details. As a bonus my now No13 had a run on the Llechfan Garden Railway at Tywyn Wharf Station. I had by this time made and fitted the side tanks but not the front and rear footplates.
On my return the remaining items were finished along with as near as possible to the real thing couplings. A driver was ordered at Llanfair and the plates from an internet supplier. I could not paint it until the plates had been drilled and fitted so it was rolling stock time. I had some old photographs of the brewery yard with the barrel trucks in various places but could only ascertain when fully loaded they held 38 standard kegs. An appeal for information on the Yahoo Modellstock Group got me a drawing of the barrel truck and the two together can be seen in the photograph.
By the time that was made the loco was ready for paint and only six weeks to Stoneleigh. The final picture shows the finished item along with the completed barrel truck.
And all with 27 days to spare according to the web site clock.
Bob Bath
Postscript
Bob’s Guinness loco won the Jack Wheldon Memorial Trophy at the 2010 National Show. In addition Bob has made the drawings for his loco available for download from the File Downloads area of the Association website.
Tim Gregson